Neuroanatomy spinal tracts Flashcards
in the DCML pathway, what is the 1st order neurone for spinal levels above T6
fasciculus cuneatus
in the DCML pathway, what is the 1st order neurone for spinal levels below T6
fasciculus gracilis
sits medially to fasciculus cuneatus
where does the DCML pathway decussate
within the MEDULLA oblongata, at the nucleus cuneatus or gracilis
where is the synapse between 2nd and 3rd order neurones in the DCML pathway
the thalamus
where do the 3rd order neurones travel in the DCML pathway
from the thalamus –> the primary sensory cortex
where do the 1st and 2nd order neurones synapse in the DCML
the nucleus gracilis and fasciculus
what is the function of the anterior spinothalamic tract
crude touch and pressure
Anterior, AJ, touch
what is the function of the lateral spinothalamic tract
pain and temperature
where do the 1st and 2nd order neurones synapse in the spinothalamic tract
synapse at the tip of the dorsal horn at the SUBSTANTIA GELATINOSA
where does the spinothalamic tract decussate
the ventral white commissure
where do 2nd and 3rd order neurones synapse in spinothalamic tract
THALAMUS - ventral posterior nucleus
where do the 3rd order neurones travel in the spinothalamic tract
thalamus –> primary sensory cortex
post central gyrus
how soon after entering the spinal cord does the spinothalamic pathway decussate
the 1st order neurone enters spinal cord, ascends 1 or 2 levels then synapses with the 2nd order neuron, which then goes on to decussate almost immediately
why is the fact the spinothalamic tract decussates very early significant
if there an injury to the spinothalamic tract in the spinal cord, it will cause contralateral symptoms as the tract has already decussated
where does the lateral corticospinal tract supply motor function to
Lateral corticospinal supplies motor to the Limbs
where does the anterior corticospinal tract supply motor function to
Anterior corticospinal supples motor to the Axial muscles
where do the pyramidal tracts originate
cerebral cortex
how many synapses does the corticospinal tract have
NONE - therefore, all pathways are described as UMN
where does the corticopsinal tract divide into anterior and lateral
the caudal aspect of medulla
where does the lateral corticospinal tract decussate
medulla
where does the anterior corticospinal tract decussate
ventral horn
when is the corticospinal tract most vulnerable to injury
as it passes through the internal capsule
paralysis of which CN causes deviation of the tongue
CN XII
does the tongue deviate to the ipsilateral or contralateral side of the lesion
tongue deviates to the contralateral side of the lesion
